The control module consists principally of electronic switches, generally made from semiconductors which cannot withstand electrostatic discharges above approximately 2 kV. Now, it frequently occurs that discharges well in excess of 2 kV, typically 20 or 25 kV, are generated in the liquid crystal display module, as a result, in particular, of the surface stresses to which it may be subjected.
As a result of this, some switches of the control module may be damaged or even destroyed.
To overcome this disadvantage, those skilled in the art have proposed the fitting of a voltage limiting component, such as a Zener diode, to each output of the control module, in such a way that the discharges can be blocked, absorbed, and then dissipated in the form of heat. However, as the number of display segments increases, the number of outputs to be fitted with these components increases, and consequently the cost of the device and its dimensions also become considerable.